Enhancement of tunneling density of states at a junction of three Luttinger liquid wires

TL;DR

This paper investigates the tunneling density of states at a junction of three Luttinger liquid wires, revealing fixed points that can enhance TDOS over a finite range, with potential for experimental observation.

Contribution

It identifies fixed points enabling TDOS enhancement at a three-wire Luttinger liquid junction, a novel phenomenon in such systems.

Findings

TDOS enhancement occurs at specific fixed points.

The enhancement range is proportional to v/(2ω).

Beyond this range, TDOS reverts to bulk value.

Abstract

We study the tunneling density of states (TDOS) for a junction of three Tomonaga-Luttinger liquid wires. We show that there are fixed points which allow for the enhancement of the TDOS, which is unusual for Luttinger liquids. The distance from the junction over which this enhancement occurs is of the order of x = v/(2 \omega), where v is the plasmon velocity and \omega is the bias frequency. Beyond this distance, the TDOS crosses over to the standard bulk value independent of the fixed point describing the junction. This finite range of distances opens up the possibility of experimentally probing the enhancement in each wire individually.